Sealing device for a bearing unit

Abstract

Sealing device for a bearing unit having at least one contact lip operatively in sliding contact with a contact surface of the bearing unit and in turn provided with a wedge portion which forms with respect to the contact surface a first angle (α) facing a medium to be contained and a second angle (β) opposite the first angle, wherein during operating conditions, the second angle (β) is smaller than the first angle (α) and with a first surface having a concave shape, the concavity of which is defined by a first radius (R1); wherein the second angle (β) is between 48° and 55° and the length of the first radius (R1) is between 2.0 mm and 10.00 mm.

The invention claimed is: 
     
       1. A sealing device for a bearing unit, comprising:
 at least one contact lip which is operatively in sliding contact with a contact surface of the bearing unit, the at least one contact lip including:
 a wedge portion which forms with respect to the contact surface a first angle (α) facing a medium to be contained, the wedge portion further forms with respect to the contact surface a second angle (β) opposite to the first angle, wherein the wedge portion is configured such that during operating conditions the second angle (β) is less than the first angle (α); and 
 a first surface, adjacent to the second angle (β), with a concave shape, the concavity of which is defined by a first radius (R 1 ). 
 
 
     
     
       2. The sealing device of  claim 1 , wherein the second angle (β) is between 48° and 55°. 
     
     
       3. The sealing device of  claim 1 , wherein the length of the first radius (R 1 ) is between 2.0 mm and 10.0 mm. 
     
     
       4. The sealing device of  claim 1 , wherein the first angle (α) is between 50° and 65°. 
     
     
       5. The sealing device of  claim 1 , wherein the first angle (α) is equal to 55° and the second angle (β) is equal to 54°. 
     
     
       6. The sealing device of  claim 1 , further comprising a third angle (γ) between a radial direction and a second surface, opposite the first surface with respect to the wedge portion, where the third angle (y) is between 50° and 65°. 
     
     
       7. The sealing device of  claim 1 , wherein a base thickness (HLT) of the contacting lip is between 0.3 mm and 1.2 mm. 
     
     
       8. The sealing device of  claim 1 , further comprising a third concave surface defined by an angle of attack (δ), formed with the radial direction, by a depth (HG) and by a third radius (R 3 ). 
     
     
       9. The sealing device of  claim 8 , wherein the angle of attack (δ) is between 20° and 35°. 
     
     
       10. The sealing device of  claim 8 , wherein the depth (HG) is between 0.1 mm and 0.5 mm. 
     
     
       11. The sealing device of  claim 8 , wherein the third radius (R 3 ) is between 0.2 mm and 0.8 mm. 
     
     
       12. A bearing unit provided with a sealing device according  claim 1 . 
     
     
       13. A sealing device for a bearing unit, comprising:
 at least one contact lip which is operatively in sliding contact with a contact surface of the bearing unit, the at least one contact lip including:
 a wedge portion which forms with respect to the contact surface a first angle (α) facing a medium to be contained, the wedge portion further forms with respect to the contact surface a second angle (β) opposite to the first angle, wherein the wedge portion is configured such that during operating conditions the second angle (β) is less than the first angle (α); and 
 a first surface, adjacent to the second angle (β), with a concave shape, the concavity of which is defined by a first radius (R 1 ), 
 
 
       wherein the second angle (β) is between 48° and 55°, and further wherein the length of the first radius (R 1 ) is between 2.0 mm and 10.0 mm. 
     
     
       14. A sealing device for a bearing unit, comprising:
 at least one contact lip which is operatively in sliding contact with a contact surface of the bearing unit, the at least one contact lip including:
 a wedge portion which forms with respect to the contact surface a first angle (α) facing a medium to be contained, the wedge portion further forms with respect to the contact surface a second angle (β) opposite to the first angle, wherein the wedge portion is configured such that during operating conditions the second angle (β) is less than the first angle (α); 
 a first surface, adjacent to the second angle (β), with a concave shape, the concavity of which is defined by a first radius (R 1 ); and 
 a third concave surface defined by an angle of attack (δ), formed with the radial direction, by a depth (HG) and by a third radius (R 3 ), 
 
 
       wherein the second angle (β) is between 48° and 55°, and further wherein the length of the first radius (R 1 ) is between 2.0 mm and 10.0 mm. 
     
     
       15. The sealing device of  claim 14 , wherein the angle of attack (δ) is between 20° and 35°. 
     
     
       16. The sealing device of  claim 14 , wherein the depth (HG) is between 0.1 mm and 0.5 mm. 
     
     
       17. The sealing device of  claim 14 , wherein the third radius (R 3 ) is between 0.2 mm and 0.8 mm. 
     
     
       18. The sealing device of  claim 14 , wherein the length of the first radius (R 1 ) is between 2.0 mm and 10.0 mm. 
     
     
       19. The sealing device of  claim 14 , wherein the first angle (α) is equal to 55° and the second angle (β) is equal to 54°. 
     
     
       20. The sealing device of  claim 14 , further comprising a third angle (γ) between a radial direction and a second surface, opposite the first concave surface with respect to the wedge portion, where the third angle (y) is between 50° and 65°.